What is pathological laughter or pathological crying?

ALS can lead to uncontrolled crying. At first, those affected (as well as their loved ones) may feel that the patient is “more emotional.” Emotional stimuli (music, movies, encounters) are associated with stronger emotional expressions, particularly crying. As the disease progresses, crying may become more intense and prolonged, which is experienced as distressing and inappropriate. Similarly, uncontrolled laughter may also occur. In strange or humorous situations, heightened or uncontrolled laughter occurs, which can also be experienced as distressing and inappropriate. Intense and prolonged laughter, in particular, can lead to misunderstandings and irritation in social interactions.

This phenomenon is referred to as “pathological laughter.” In both cases—uncontrolled crying and laughter—there is a discrepancy between the “normal” cause for crying or laughing and the exaggerated motor expression of the crying or laughter. In very rare cases, uncontrolled yawning may occur instead of crying and laughing. The totality of these phenomena (uncontrolled crying, laughing, and yawning) is described as “motor disinhibition.”

The need for treatment of motor disinhibition depends largely on the extent to which those affected find the symptom distressing—both for themselves and in their interactions with others. Several medications are options for treatment.